Seed Treatment:
• Cold stratification: Mix seeds with moist sand or vermiculite, place in a sealed plastic bag, and refrigerate at 35–40°F (1–4°C) for 4–6 weeks.
• Alternatively, direct sow outdoors in late fall to allow natural winter stratification.
• Seeds are tiny and require light to germinate — do not cover with soil.
When to Sow:
• Indoors: Sow 6–8 weeks before your last frost date after cold stratifying.
• Outdoors: Direct sow in early spring or late fall for natural stratification.
Sowing Instructions:
• Surface sow onto moist, well-draining seed-starting mix.
• Do not cover seeds; gently press them into the soil surface.
• Keep soil consistently moist but not soggy.
• Germination typically occurs in 14–28 days at 60–70°F (16–21°C).
Light Requirements:
• Prefers full sun to partial shade.
• In hotter climates, light shade can help prevent wilting.
Soil Requirements:
• Thrives in moist, well-drained soils.
• Tolerates poor to moderately fertile soils.
• pH range: 6.0–7.5.
Watering:
• Keep soil evenly moist during germination and early growth.
• Once established, it is relatively drought-tolerant, but occasional watering encourages more blooms.
Spacing:
• Thin or transplant seedlings to 12 inches (30 cm) apart.
Growing Tips:
• Produces elegant purple-blue, star-shaped flowers on slender stems from late spring to mid-summer.
• Attractive to bees and butterflies.
• Excellent for wildflower gardens, cottage borders, and naturalized areas.
• A biennial or short-lived perennial that may self-seed in suitable conditions.
• Hardy in USDA Zones 3–8.